Measuring Tool of Choice Question
 

For measuring the housing bores of a GM 12 bolt housing?

My Mitutoyo 2"-6" dial bore gauge is too long to work inside the carrier area to take a measurement and I want to do this measurement checking on my own before sending out the housing for some work.

Any recommendations?

Thank you in advance.

Snap gauge and a micrometer. Check and recheck to get feel of snap gauge. Measure new bearing race will atleast compare dimentions if mic is not qualified. Check multiple directions in bore for out of round.

^This

Try these.

Yes, but don't get them from Amazon, its owner does not need any more income!

it depends...do you have a set of outside micrometers?

HOW close are you looking to measure it +/- .001 or +/- .0002

If YES...then snap gauges can be your friend. WARNING cheap gauges measure cheaply. The basic rule of use with snap gauges is you gotta measure 3 times.... 2 times should be the same and 1 will probably be smaller number. Just saying your damn right there is a difference between BRAND UNKNOWN and Starrett.
If you have never used "snap" gauges ....its a feel/process to repeat within .001 (ill advised for beginners shooting for +/- .0002 measuring)
If NO then I would recommend an I.D. mic set https://www.mscdirect.com/product/details/86424983

Price is a bit hard to swallow for minumal use??? These are tools of my trade for the last 35 yrs. and YES they do last a lifetime (didn't cost that much back in 1987...lol)

I do have outside mic's.

All of my measuring tools are Mitutoyo brand. I took this threads advice and went at it with a Mitutoyo snap gauge and a 3-4" outside mic positioned in a mic holder from Goodson.

Trying to cut Mark Williams' billet caps to the nominal published spec of 3.0625 with a +/- variance of .001.

I am good to go.

Thanks everyone.

time to get some inside mic's

About telescoping gages, after you swing them and take them out, you will place one end on the mic bottom and swing the top of the gage while turning the mic smaller until it just touches. Now your reading is actually .0005 larger than the hole. This is because if you take that gage and swing it in back the hole again, you will feel tension on the telescoping gage. To get the same tension on the mic you would need to turn the mic .0005 smaller.

You could purchase used inside mics and save some $$$